fix(kez-chat/web): emoji picker pops up as overlay instead of squeezing compose

Bug: I was appending the <emoji-picker> custom element to the OUTER
wrapper div (which is part of the flex compose row), so when the picker
opened it became a flex sibling of the button and pushed the text
input + Send button down to a tiny strip.

Fix: append into the absolute-positioned popover container (new
popoverEl ref) instead of the wrapper. The popover is taken out of
flow so the compose row stays put and the picker floats above it.

Also:
- Outer wrapper gets shrink-0 so it doesn't expand even if the picker
  somehow leaks.
- Click-outside check now looks at both wrapEl AND popoverEl (since
  the picker is no longer a descendant of the wrapper).
- Popover anchors bottom-full left-0 — picker grows up and to the
  right of the 😀 button.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

kez-chat/web/src/lib/EmojiButton.svelte

@@ -13,7 +13,10 @@
   let { onpick }: Props = $props();
 
   let open = $state(false);
-  let mountEl: HTMLDivElement | null = $state(null);
+  /** Outer wrapper — captures the document-click bounds (must include the button). */
+  let wrapEl: HTMLDivElement | null = $state(null);
+  /** Floating popover container — where the <emoji-picker> custom element mounts. */
+  let popoverEl: HTMLDivElement | null = $state(null);
   let pickerEl: HTMLElement | null = null;
   let loading = $state(false);
   let loadError = $state<string | null>(null);
@@ -33,15 +36,21 @@
         pickerEl.addEventListener("emoji-click", onEmojiClick as EventListener);
         // Match the dark-on-light scheme of the rest of the app.
         pickerEl.classList.add("light");
-        if (mountEl) mountEl.appendChild(pickerEl);
       } catch (e) {
         loadError = (e as Error).message;
       } finally {
         loading = false;
       }
-    } else if (mountEl && !mountEl.contains(pickerEl)) {
-      mountEl.appendChild(pickerEl);
     }
+    // Mount into the floating popover div on every open — the popover
+    // is conditionally rendered, so it's a fresh DOM node each time.
+    // Wait a tick so the {#if open} block actually mounts before we
+    // try to appendChild into it.
+    queueMicrotask(() => {
+      if (pickerEl && popoverEl && !popoverEl.contains(pickerEl)) {
+        popoverEl.appendChild(pickerEl);
+      }
+    });
     document.addEventListener("click", onDocumentClick);
   }
 
@@ -58,7 +67,10 @@
 
   function onDocumentClick(ev: MouseEvent) {
     // Close when the user clicks anywhere outside the popover or trigger.
-    if (mountEl && !mountEl.contains(ev.target as Node)) close();
+    const t = ev.target as Node;
+    const inside =
+      (wrapEl && wrapEl.contains(t)) || (popoverEl && popoverEl.contains(t));
+    if (!inside) close();
   }
 
   onDestroy(() => {
@@ -67,7 +79,10 @@
   });
 </script>
 
-<div class="relative" bind:this={mountEl}>
+<!-- `relative` here is purely a positioning anchor for the absolute
+     popover — the popover itself is taken out of flow so it doesn't
+     squeeze the rest of the compose row. -->
+<div class="relative shrink-0" bind:this={wrapEl}>
   <button
     type="button"
     class="px-2 py-2 text-xl border border-gray-300 rounded hover:bg-gray-50 leading-none"
@@ -82,15 +97,16 @@
 
   {#if open}
     <div
-      class="absolute bottom-full right-0 mb-2 z-50 shadow-lg rounded overflow-hidden bg-white"
+      bind:this={popoverEl}
+      class="absolute bottom-full left-0 mb-2 z-50 shadow-lg rounded overflow-hidden bg-white"
     >
       {#if loading}
         <div class="p-4 text-xs text-gray-500">Loading…</div>
       {:else if loadError}
         <div class="p-4 text-xs text-red-700">Failed: {loadError}</div>
       {/if}
-      <!-- The actual <emoji-picker> custom element is appended here
+      <!-- The <emoji-picker> custom element is appended into this div
-           imperatively by togglePicker() so we can control its lifecycle. -->
+           imperatively by togglePicker() so we control its lifecycle. -->
     </div>
   {/if}
 </div>